No abstract

The anatomy of the corpus callosum has received renewed interest during recent years due to the increasing number of callosotomies performed to treat intraventricular lesions, as well as some forms of generalized epilepsy. We have previously reported on the microsurgical anatomy of the corpus callosum and identified specific anatomical reference landmarks that can be used during surgery. In the present study we have continued the anatomical aspect of this earlier work in a larger number of cases, with in vitro observations (brain out of skull) being compared with the corresponding in vivo features seen in sagittal MRI slices. Fifty-three in vitro microsurgical callosotomies was performed and the data collected compared with a series of 57 in vivo normal MR callosal images. Callosal dimensions were measured on both the anatomical and MRI material, thus overcoming the problems associated with in vitro callosal deformation. Of the anatomical landmarks studied the distance from the genu of the corpus callosum to the bifurcation of the columns of the fornix was found to be useful for the intraoperative evaluation of the extent of rostral callosotomy, as it is not significantly changed in in vitro. The main microsurgical features of rostral callosotomy are presented.

No abstract

Corpus callosotomy was reported for the first time by Dandy in 1922 and developed by Van Wagenen and Herren in 1940, but only Wilson in 1975 started performing it with a microsurgical technique. Its indications have remained controversial for a long time, but during the last years new interest has been raised concerning callosotomy as a treatment for some kinds of generalized epilepsy or as route to the anterior ventricular system. The microsurgical anatomy of the corpus callosum has therefore regained interest. With this goal in mind, the authors studied some aspects of the microsurgical anatomy of the corpus callosum, namely its dimensions, variability and topography, as well as the transcallosal access to the deep interfrontal region and to the third ventricle. This study was carried out on 30 normal adult brains, obtained from routine autopsies, that were submitted to a special preparation procedure and dissected with microsurgical technique. The main aspects of the operating features, the measurements made and the variation in the different parameters are described. Some references are proposed respecting the extent of anterior partial and subtotal callosotomy.